It’s no wonder that Christmas decoration choices largely come down to evergreen plants—after all, the holiday originated in those parts of Europe that are mostly dark and gloomy in the winter months, and especially so around winter solstice.
But if you've come to think that mistletoe has dark green, spiny leaves and bright-red berries, you’ve fallen victim to popular culture that gets its botany terribly wrong. Mistletoe (Viscum album) is a partially parasitic shrub native to Europe that lives on the stems of other trees, such as hawthorn and linden. It has translucent white berries and rounded yellow-green leaves (see photo above).
This is holly, not mistletoe—although the two are sometimes pictured together.
The spiky holly (Ilex aquifolium), on the other hand, is a small tree traditionally associated with Christian symbolism. Its evergreen properties and decorative berries make it an attractive Christmas decoration, but it’s not the one people stand underneath to elicit kisses.
And what’s the deal with kissing under a bouquet of parasitic shrubbery? Mistletoe has been hung in households for centuries, and references to the sacred plant and its healing properties can be found in many accounts of both Celtic and Norse mythology.
According to the writings of Roman scholar Pliny the Elder, ancient druids had a religious ritual in which white-clad druids climbed a sacred oak to harvest mistletoe with a golden sickle, ritually sacrifice two white bulls, and prepare a potion from the harvested shrub that can be an antidote to all poisons, and also aid fertility. In Norse mythology mistletoe is tied to the story of the death of Baldur, son of Odin, who was killed by the trickster god Loki with a mistletoe branch. There are several versions of the tale, but in one of them Baldur returns to life, prompting his mother Frigga to declare the mistletoe a symbol of love.
The exchange of Christmas kisses under a mistletoe dates back to at least the 18th century, although some accounts trace its history all the way back to the Roman pagan festival of Saturnalia. In its modern incarnation the tradition holds that if a person caught standing under a mistletoe refuses a kiss, it will be bad luck. As you can imagine, it's a useful ritual for Victorian youths whose courting and even touching rules were much stricter than today.